>> I have ra1d1 setup as follows.
>>
>> MD3, 20 GB as / (SDA2, SDC2)
>> MD4, 267 GB as /home (SDA3, SDC3)
>> Swap as SDA5 1 gb and SDC5 1 gb
>>
>> Installation went fine on installation, but on reboot, it says disk has
>> no operating system.
>>
>> What did I do wrong and how can I fix it?
>>
>>
>
> Without more info I would check to make sure that you have the right disk
> set to boot from in the bios. I had this problem ones and had to set it to
> boot from device / driver that the raid setup was on in the bios.
>
> Jack Malone

By default, opensuse wants to install grub onto the root partition.
However, with an md root, that won't work.

Basically, you need to boot into the rescue system, get the md array up,
bind /proc and /dev into it, and then install grub onto the MBR.

(I'm typing those commands out from memory, so I may have the syntax
slightly wrong, but it should be pretty close.)

Getting the MD array up is a little tricky. Once you're in the rescue
system, you need to edit /etc/mdadm.conf, and add the lines
DEVICE /dev/sda2
DEVICE /dev/sdc2

Then you can do `mdadm --examine --scan`, and it should find the array.
Verify that the correct info is output to the console, and if so do `mdadm
--examine --scan >> /etc/mdadm.conf`, and then `mdadm --activate --scan` to
get the array active.

In the grub shell, do
`root (hd0,1)`
And then
`setup (hd0)`
`setup (hd2)`

That should get the correct config installed onto the MBR of the disks.
Note that by doing the setup for both hd0 and hd2, you've got the boot info
installed on the MBR of sdc as well; that way, if the first disk fails, you
don't need to repeat this process -- your machine will be bootable using the
remaining disk.

(yes, setting root to (hd0,1) is counterintuitive, since that's just a RAID
member. But, it works...)

This process is actually one of the things that drives me batty about
opensuse. I'm using it in a production environment, and have bunches of
machines with md roots, and have to do this with every single one of them.
The bootloader installation part of the installer is simply incapable of
dealing with an install onto the MBR of two separate disks. I don't know
why, but it is.